Ammunition round



g- 3, 1967 F. G. LARSEN AMMUNITION ROUND Filed Dec. 1, 1965 INVENTOR.

' FARRELL (s. LARSEN Wm M ' ATTORNEY United States Patent 3,334,588 AMMUNITION ROUND Farrell G. Larsen, San Jose, Calif., assignor to General Precision, Inc., Binghamton, N.Y., a corporation of Delaware Filed Dec. 1, 1965, Ser. No. 510,812 9 Claims. (Cl. 102-42) This invention relates to fire arms; and more particularly, this invention provides an improved round of ammunition containing a plurality of projectiles which are launched simultaneously in a flight pattern.

Heretofore, shotguns have been used to launch a pattern of shot from a single catridge or ammunition round. The shot is launched through the barrel of a gun ahead of a wad of material which is accelerated by a propellant charge. Attempts have been made to similarly launch a pattern of flechettes or dart projectiles from a shotgun, and flechettes have been launched in a simple sabot which is torn apart by aerodynamic forces when the package emerges from the muzzle of the gun. However, it has been found that the opening of the sabot, after launch, tends to spread the configuration of projectiles causing wide dispersion thereof such that the projectiles do not travel in a tight pattern. The dispersal of projectiles caused by the aerodynamic destruction of the sabot destroys the accuracy and effectiveness of a weapon using flechetts in a simple tear-apart sabot. A sabot of this type is disclosed in a co-pending patent application, Ser. No. 380,177, now abandoned filed on July 3, 1964, by Donald E. Davenport entitled Finless Dart for Firearm Projectile.

It is an object of this invention to provide an improved round of ammunition wherein a plurality of projectiles may be launched without undue dispersion when the projectiles are released from a sabot.

Another object of this invention is to provide a sabot arrangement wherein the projectiles are initially confined within a container, and after launch, are permitted to move forwardly from the projectile container which remains intact except for the removal of a forward cap thereof. 7

Another object of this invention is to provide a round of ammunition wherein a plurality of projectiles are contained within a central chamber of a sabot which is formed to have a high aerodynamic drag, and more particularly, it is an object to provide an arrangement for opening the sabot at the forward end only such that the relatively heavy or massive projectiles may move forwardly out of the sabot after launch when the aerodynamic forces cause the sabot to decelerate.

Numerous other objects and advantages will be apparent throughout the progress of the specification which follows. The accompanying drawing illustrates a certain exemplary embodiment of the invention and the views therein are as follows:

FIGURE 1 is a cross-sectional view of a round of ammunition containing spherical shot within the chamber and barrel of a launching weapon;

FIGURE 2 is a similar cross-sectional view of another round of ammunition containing flechette projectiles; and

FIGURE 3 is a section along the plane 33 of FIGURE 2 showing the forward end of the ammunition round.

Briefly stated, according to preferred embodiments of this invention, an ammunition round includes a cartridge case 11 with a propellant charge 12 and a sabot 13 which may be launched forwardly through a gun barrel 14. The sabot may be formed of plastic and may have an inner cylindrical chamber 15 and an outer cylinder 16 concentric therewith. Both cylinders are closed at the rearward ends thereof and are open at the forward ends. A

Patented Aug. 8, 1967 projectile container 17 is a cylinder closed at the rearward end and movably positioned within the central chamber 15 of the sabot 13. A wad or pad of compressible material 18 is positioned within the rearward end of the central chamber of the sabot and resiliently engages the projectile container 17 normally holding the projectile container in a forward position within the central chamber of the sabot. A cap 20-21 is positioned to close the forward end of the projectile container 17 to hold the projectiles therein. When the ammunition round is fired, the sabot 13 is propelled forwardly through the gun barrel 14 with great acceleration. During launch, the force of inertia acting upon the relatively heavy or massive projectiles, moves the projectile container 17 rearwardly within the central chamber 15 of the sabot thereby compressing the material 18. The forward ends of the inner cylinder 15 of the sabot is formed with projecting edges or points 22 which impinge upon the cap 20 to break the cap away from the projectile container 17 thereby releasing the projectiles within the container. The outer cylinder 16 of the sabot is open at the forward end to provide cups having a high aerodynamic drag such that the sabot will decelerate rapidly after emerging from the gun barrel 14. Since the cap 20-21 has been disengaged from the projectile container 17, the relatively heavy or massive projectiles will move forwardly and emerge from the projectile container through the end opened by the removal of the cap 20. Since the projectiles may emerge directly from the forward end of the sabot, there is no force tending to disperse the configuration of projectiles and to separate one from the other. Therefore, the projectiles will continue to move forwardly without undue scattering in straight flight toward the target.

The sabot 13, projectile container 17, and cap 20 may be formed of plastic material. The compressible material 18 may be composition cork. Of course, the. projectiles are metallic and are therefore heavy and massive as compared to the remainder of the package which is propelled through the barrel 14 of the launching weapon. Therefore, it may be appreciated that during launching acceleration, the inertia of the relatively massive projectiles will move the projectile container 17 rearwardly in the sabot; and that after launch, the heavy projectiles will separate from the projectile container to continue a straight flight'path which will be independent of the path of the rapidly decelerating sabot.

FIGURES 1 and 2 show an ammunition round in accordance with this invention which has been placed into the chamber or barrel 14 of a firing weapon. A breach block 24 closes over the end of the barrel, and a firing pin 25 is positioned to detonate the round. A detonating charge 26 is positioned for impingement by the firing pin to cause detonation of the propellant charge 12. The catridge shown in FIGURE 1 includes a chamber for containing the propellant charge 12 having a series of holes or aperatures 27 through which the gaseous combusion products of the propellant may build up a pressure to propel the sabot. During launch, the pressure in the chamber behind the sabot 13 propels the sabot forwardly (to the right as shown in FIGURES 1 and 2). A gas seal ring or collar 28 is positioned around a rearwardly extending shoulder 29 of the sabot. The gas seal ring is of a flexible plastic which will be expanded outwardly by the gas pressure to create a seal between the sabot and the gun barrel 14 as the sabot is ejected from the cartridge case.

As indicated heretofore,-the sabot comprises two concentric cylinders. The inner cylinder 15 is dimensioned to hold the projectile container 17, while the outer cylinder 16 is dimensioned to conform with the diameter or caliber of the gun barrel 14. Both cylinders are closed at the rearward ends thereof. As shown in FIGURE 3,

reinforcing webs 30 connect between the inner cylinder and the outer cylinder to give rigidity and strength to the structure of the sabot. It may be appreciated that the open forward end of the space between the inner and outer cylinders provides a series of air pockets or cups 31 which will have high aerodynamic drag when the sabot has emerged from the muzzle of the launching weapon.

During launch, the sabot is propelled through the gun barrel 14, the entire sabot assembly including the projectile container 17 is accelerated. The relatively heavy projectiles cause the projectile container 17 to move rearwardly (to the left as shown in FIGURES 1 and 2), compressing the material 18. The forward projections 22 f the inner cylinder will impinge upon the cap -21. As shown in FIGURE 1, the projectiles are balls of shot 33 and the cap 20 may be a cup shaped structure closing snugly over the open end of the projectile container 17 similar to a cap on a plastic medicine container. During launch, the projections 22 impinge the cap 20 and disengage the cap from the projectile container 17. After the sabot of FIGURE 1 has emerged from the barrel of the gun, the aerodynamic drag caused by the pockets 31 will cause a rapid deceleration of the sabot, and the spherical shot balls 33, having substantially greater mass than the plastic sabot will move forwardly separating from the now open end of the projectile container and will continue a flight path apart from the decelerating sabot. It has been found that the presence of the cap 20 in a position forwardly of the spherical balls is not particularly detrimental, since the cap will tilt and will slide away from the flight path of the balls without unduly dispersing the balls.

The projectile container 17 may be formed with two longitudinal slots or openings and a retainer disc 34 may be ineserted into the rearward end of the projectile container 17. The retainer disc 34 is provided with two diametrical opposed tabs which extend obliquely through the slotted openings 35 and will engage the walls of the inner cylinder 15 of the sabot. The oblique tabs will permit the projectile container 17 to shift rearwardly under launching acceleration, but will prevent the projectile container from moving forwardly with respect to the sabot 13. The obliquely extending tabs 36 will dig into the cylinder walls of the sabot to resist any forward movement of the projectile container 17. The retainer disc 34 with the oblique tabs '36 constitutes a friction lock or means for retaining the projectile container within the sabot. Therefore, after launch, the projectile container remains locked to the decelerating sabot while the projectiles move out of the uncovered forward end thereof.

FIGURE 2 shows a bundle of fiechettes 37 Within the projectile container 17. The cap 21 is formed of a brittle plate material such as acrylic plastic. In this case, the projectile container 17 may be provided with a pair of forwardly extending tabs 39, and the brittle cap 21 is provided with mating holes to receive the tabs with a snug fit to secure the cap to the sabot. The cap 21 is scored as shown at 40 to provide a weakened section extending across a diameter thereof. When the sabot is launched, the projectile container will move rearwardly compressing the material 18 and a pair of forwardly extending edges or points 22 will impinge upon and break the cap 21 into two halves alony the scored or weakened ldiameter. After the assembly has emerged from the muzzle of the launching weapon and the sabot is decelerated, the fiechettes will move forwardly out of the projectile container while the two halves of the broken cap 21 fall away on either side thereof.

As indicated above, the presence of an unbroken cap 20 ahead of the shot balls 35 is not detrimental because the combination of the cap followed by the balls is aerodynamically unstable such that the cap will separate from the balls. On the other hand, it has been found to be necessary to physically break the cap 21 of the flechette container of FIGURE 2. If the cap 21 were not broken the bundle of fiechettes would remain intact since the fiechettes behind the unbroken cap would be aerodynamically stable and would remain as a unit in flight. The group fiechettes would move as a single projectile behind an unbroken cap and would not provide a desirable projectile pattern.

The sabot arrangement of this invention provides a means for holding a plurality of projectiles intact during the acceleration of launch, and for releasing the projectiles without undue dispersal after launch by aerodynamic drag. This invention provides a stability not heretofore attained with an ordinary sabot which is disintegrated after launch. While the disintegration of an ordinary sabot creates forces which tend to disperse the individual projectiles, the sabot of this invention decelerates and removes itself rearwardly from the configuration of projectiles with a minimum disturbance to the configuration.

Changes may be made in the form, construction and arrangement of the parts without departing from the spirit of the invention or sacrificing any of its advantages, and the right is hereby reserved to make all such changes as fall fairly within the scope of the following claims.

The invention is claimed as follows:

1. A round of ammunition comprising a sabot having a central chamber, a projectile container positioned within the central chamber of the sabot, and a plurality of projectiles within the projectile container, said projectile container having a cap closing a forward end thereof, said sabot having resilient means normally retaining the projectile container in a forward position with respect to the central chamber of the sabot, said resilient means being operable to permit the projectile container to move rearwardly in the central chamber when the sabot is accelerated during launch, said sabot including means for disengaging the cap from the projectile container when the projectile container moves rearwardly in the central chamber thereof.

2. A round of ammunition comprising a sabot having a central chamber, a projectile container movably positioned within the central chamber of the sabot, and a plurality of projectiles within the projectile container, said projectile container having a cap closing a forward end thereof, said central chamber of the sabot containing a compressible material for normally holding the projectile container in a forward position and for allowing the projectile container to move rearwardly in the central chamber when the sabot is accelerated during launch, said sabot including means for impinging upon and for disengaging the cap from the projectile container when the projectile container moves rearwardly in the central chamber thereof.

3. A round of ammunition in accordance with claim 2 wherein the projectile container includes a means for frictionally locking the projectile container to the central chamber of the sabot to prevent the projectile container from moving forwardly with respect to the sabot.

4. A round of ammunition in accordance with claim 3 wherein the projectiles comprise spherical balls.

5. A round of ammunition in accordance with claim 3 wherein the projectiles comprise fiechettes.

6. A round of ammunition comprising a sabot being formed of an inner cylinder and an outer cylinder coaxial therewith, a cylindrical projectile container movably positioned within the inner cylinder of the sabot, a plurality of projectiles within the projectile container, said projectile container having a cap closing a forward end thereof, a compressible material positioned within the rearward end of the inner cylinder of the sabot and bearing against the projectile container whereby the projectile container is normally held in a forward position within the inner cylinder of the sabot, said compressible material being operable to compress under forces of inertia exerted by the projectile container during launching acceleration whereby the projectile container will move rearwardly within the inner cylinder when the sabot is launched, the inner cylinder of the sabot being formed with at least one forwardly extending projection for impinging upon the cap and for disengaging the cap from the projectile container when the projectile container moves rearwardly during launch.

7. A round of ammunition in accordance with claim 6 wherein the cap of the projectile container is cup-shaped and dimensioned to fit snugly over the forward end of the projectile container whereby the forward projection of the inner cylinder of the sabot will press the cap forwardly during launch to remove the cap from the projectile container.

8. A round of ammunition in accordance with claim 6 wherein the cap of the projectile container is formed of breakable material, said cap being scored across a diameter thereof to provide a weakened section along which the cap will break, and wherein the inner cylinder of the sabot is formed with two forwardly projecting edges positioned to impinge upon the scored diameter of the cap during launch whereby the cap will break into two halves to release the projectiles subsequent to launch.

9. A round of ammunition comprising a sabot being formed of plastic and having an inner cylinder and an outer cylinder coaxial therewith, rearward ends of both cylinders being closed, reinforcing webs connecting between the inner cylinder and the outer cylinder to provide cavities with high aerodynamic drag, a cylindrical projectile container having a rearward end closed being movably positioned within the inner cylinder of the sabot, a; metallic disc positioned within the projectile container and having tabs protruding obliquely therefrom for engagement with the inner cylinder of the sabot whereby the projectile container is prevented from moving forwardly within the sabot, a plurality of projectiles within the projectile container, said projectile container having a cap closing the forward end thereof, and retaining the projectiles therein, a compressible material positioned within the rearward end of the inner cylinder of the sabot and bearing against the projectile container whereby the projectile container is normally held in a forward position within the inner cylinder of the sabot, said compressible material being operable to compress under forces of inertia exerted by the projectile container and the projectiles therein during launching acceleration whereby the projectile container will move rearwardly within the inner cylinder when the sabot is launched, the inner cylinder of the sabot being formed with forwardly extending projections for impinging upon the cap and for breaking the cap from the projectile container when the projectile cont-ainer moves rearwardly during launch whereby the projectiles will be released from the projectile container after launch when the aerodynamic drag decelerates the sabot.

No references cited.

SAMUEL FEINBERG, Primary Examirter.

ROBERT F. STAHL, Examiner. 

1. A ROUND OF AMMUNITION COMPRISING A SABOT HAVING A CENTRAL CHAMBER, A PROJECTILE CONTAINER POSITIONED WITHIN THE CENTRAL CHAMBER OF THE SABOT, AND A PLURALITY OF PROJECTILES WITHIN THE PROJECTILE CONTAINER, SAID PROJECTILE CONTAINER HAVING A CAP CLOSING A FORWARD END THEREOF, SAID SABOT HAVING RESILIENT MEANS NORMALLY RETAINING THE PROJECTILE CONTAINER IN A FORWARD POSITION WITH RESPECT TO THE CENTRAL CHAMBER OF THE SABOT, SAID RESILIENT MEANS BEING OPERABLE TO PERMIT THE PROJECTILE CONTAINER TO MOVE REARWARDLY IN THE CENTRAL CHAMBER WHEN THE SABOT IS ACCELERATED DURING LAUNCH, SAID SABOT INCLUDING MEANS FOR DISENGAGING THE CAP FROM THE PROJECTILE CONTAINER WHEN THE PROJECTILE CONTAINER MOVES REARWARDLY IN THE CENTRAL CHAMBER THEREOF. 